Nikki Bella's niece Birdie will be a "flower girl" at her wedding when she ties the knot with John Cena in 2018.

The 33-year-old professional wrestler is set to tie the knot with her fiancé John Cena next year, and has said her two-month-old niece Birdie - whose parents are Nikki's twin sister Brie and her husband Daniel Bryan - will play a major role in the ceremony.

When asked by E! News if Birdie will be made a flower girl, the 'Total Divas' star said: "Yes. John has three nieces, so we're going to have them as flower girls and then my brother's little girl Vivienne and then Birdie. We'll probably get Birdie a really special dress."

To which Brie added: "Yes, we have to! We have to make sure she says yes to the dress."

The news comes after fellow wrestler John - who asked Nikki to marry him back in April at WrestleMania 33 - confirmed their wedding would likely take place in 2018 as they have to work around their "super busy" schedules.

He said: "The speed of everything is directly dependent on Nicole. I'm one of those guys where it took me five years to get down on one knee, so I'm ready to go, but I also know there's a lot into planning that day and since it's taken so long, it should be absolutely everything that both of us want.

"We are both super, super busy and it just has to be right. I really, really want to say I hope it's gonna be next year sometime, but also I want to do it when it's right for Nicole and she can get the most out of it as well."

Meanwhile, although Brie recently welcomed her tot into the world, Nikki might not be following suit as John doesn't believe he'll make a good father.

Asked if his stance on having a baby has changed, he said: "Right now it hasn't changed. I can barely raise myself, so I just don't know how good a dad I'll be. I guess that's my biggest fear."